That's because there isn't supposed to be a box 7 on the 1099-MISC. Box 7 is just a tickmark box that says "Payer made Direct sales totaling $5000 or more of consumer products to recipient for resale." The amount paid to your wife should be in box 3.
Here is a link to the current form 1099-MISC. If your form doesn't match this then you need to have your wife inform the brokers that she's working for that they've used the wrong form.
@cbmarsh
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